1. Field of the Invention
This invention relates to the field of intravascular medical devices and their methods of production, and more particularly to the field extruding tubular parisons for use in the manufacture of catheters and components thereof such as: angioplasty, balloon, neurological and guide catheters, among others, which may be used in various medical procedures such as percutaneous transluminal angioplasty (PTA), percutaneous transluminal coronary angioplasty (PTCA) as well as in procedures involving the placement of medicines and medical devices within the body.
Some embodiments of the invention are directed to all forms of catheters which may be advanced through a body lumen or vessel. Some examples of catheters are over-the-wire (OTW) catheters, such as are described in U.S. Pat. No. 5,047,045; single-operator-exchange (SOE) balloon catheters, such as are described in U.S. Pat. Nos. 5,156,594 and 5,549,552. Other examples of catheters which may utilize the unique features of the present invention are described in U.S. Pat. Nos. 5,938,653, 5,897,537, among others.
2. Description of the Related Art
Intravascular diseases are commonly treated by relatively non-invasive techniques such as PTA and PTCA. These angioplasty techniques typically involve the use of a balloon catheter. In these procedures, a balloon catheter is advanced through the vasculature of a patient such that the balloon is positioned proximate a restriction in a diseased vessel. The balloon is then inflated and the restriction in the vessel is opened. In other uses a catheter may be used to deliver an endoprosthesis such as a stent, graft, vena cava filter or other implantable device. Where an implantable device is to be delivered into a body lumen the catheter may include one or more inflatable portions or balloons.
Many procedures make use of a guide catheter positioned within the vascular system of a patient. The guide catheter assists in transporting a balloon dilation catheter, or other form of treatment device, to the portion of the vessel requiring treatment or inspection. The guide catheter is urged through the vasculature of the patient until its distal end is proximate the restriction. The balloon catheter may then be fed through a lumen in the guide catheter.
Whether an individual procedure utilizes a guide catheter or simply requires the use of a solitary dilatation or medical device delivery catheter, one catheter typically must possess a level of rigidity which will allow it to traverse tortuous pathways through blood vessels in a manner that minimizes trauma. The catheter must be capable of being advanced through the vascular system without folding or buckling despite application of longitudinal and/or rotational forces upon the catheter. Because many catheters have the desired rigidity, it may be desirable to incorporate flexibility and/or other desired characteristics into the catheter shaft. These sorts of improvements can be made through the application of one or more coatings to a catheter or portions thereof. For example, U.S. application Ser. No. 09/504,194 to Wang et al, filed Feb. 15, 2000, the entire content of which being incorporated herein by reference, describes a method of coating extruded polymeric tubes used in medical devices.
In some cases however, it may be desired to provide at least a portion of a catheter, particularly the distal tip with selected physical properties without the use of a coating. For example in U.S. application Ser. No. 09/965,765 to Yang et al, a distal tip of a catheter is preferably constructed from a coextrusion of at least two materials having different material characteristics such as hardness. The combination of materials is intended to provide the catheter tip with sufficient rigidity to avoid kinking and bending as it is advanced through a lumen, but to also provide the tip with sufficient flexibility so that the tip is less likely to cause trauma to vessel surfaces which it may contact.
The present invention seeks to provide a tubular member such as a balloon with desired physical characteristics by constructing the balloon or other member from a matrix of a first material with one or more stripes of at least one other material.
All US patents and applications and all other published documents mentioned anywhere in this application are incorporated herein by reference in their entirety.
Without limiting the scope of the invention, a brief summary of some of the claimed embodiments of the invention is set forth below. Additional details of the summarized embodiments of the invention and/or additional embodiments of the invention may be found in the Detailed Description of the Invention below.
A brief abstract of the technical disclosure in the specification is provided as well only for the purposes of complying with 37 C.F.R. 1.72. The abstract is not intended to be used for interpreting the scope of the claims.